Japanese eel (Anguilla japonica Temminck & Schlegel, 1846) propagation using cryopreserved sperm samples

The aim of this study was to test the artificial seminal plasma (ASP) as the extender as well as methanol as the cryoprotectant for cryopreservation, and to collect information on the fertilizing capacity of cryopreserved sperm samples. Eggs from Japanese eel, Anguilla japonica, females were control‐fertilized with native sperm diluted with ASP and cryopreserved sperm (ASP as extender [in 1:100 ratio] and 10% methanol in v/v final concentration). No statistical differences (p < .05) were among the measured parameters (hatching, survival after 10 days post‐hatch, malformation rates) between the two groups, thus this cryopreservation method can be used effectively for artificial propagation of the Japanese eel, Anguilla japonica.     

Base tilt of poly[d(A)]-poly[d(T)] and poly[d(AT)]-poly[d(AT)] in solution determined by linear dichroism

We have measured the CD, isotropic absorption, and LD of poly[d(A)]–poly[d(T)] and poly[d(AT)]–poly[d(AT)] in the vacuum-uv spectral region. The reduced dichroism (LD divided by isotropic absorption) varied as a function of wavelength and was independent of shear gradient. Thus, the bases are not perpendicular to the helix axis in solution. Since the directions of the transition dipoles are known, the orientations of the bases in the polymers can be calculated from the reduced dichroism spectra. The results show that the base normals are tilted at angles greater than 25°, with respect to the helix axis, and thymine is tilted more than adenine for both polymers. The tilt axes of adenine and thymine are not parallel, indicating a large propeller twist. Space-filling models of poly[d(A)]–poly[d(T)] and poly[(AT)]–poly[d(AT)] are built based on our results, and the conformations of the two (A + T) polymers in solution are discussed.     

Base tilt of B-form poly[d(G)]-poly[d(C)] and the B- and Z-conformations of poly[d(GC)]-poly[d(GC)] in solution

We have measured the CD, isotropic absorption, and linear dichroism (LD) in the vacuum-uv spectral region for the B-conformations of poly[d(G)]-poly[d(C)] and poly[d(GC)]-poly[d(GC)], and for the Z-conformation of poly[d(GC)]-poly[d(GC)] formed in 70% trifluoroethanol. The reduced dichroism (LD divided by isotropic absorption) for all conformations varied with wavelength, indicating that the bases are not perpendicular to the helix axis. Since the directions of the transition dipoles are known, the inclinations and axes of inclination of each base can be determined from the wavelength dependence of the reduced dichroism spectra. The results indicate that the base normals of the (G + C) polymers in the B- and Z-conformations are tilted at angles greater than 19° with respect to the helix axis. The guanine and cytosine bases have different inclinations, and the tilt axes are not parallel. Therefore, the bases for all the (G + C) polymer conformations studied are buckled and propeller twisted.     

Age and growth of damselfish Chromis notata (Temminck & Schlegel, 1843), Jeju Island,Korea

This study investigated the age and growth of damselfish, Chromis notate, from Jeju Island in Korea. Samples were collected monthly by lift net from September 2013 to August 2014. Total lengths of the damselfish ranged from 6.4 to 15.3 cm. The relationship between total length and wet weight was WW = 0.0125TL^3.1631 for females, and WW = 0.0091TL^3.2769 for males. The slopes in the relationship between length and weight were not significantly different between sexes, but were significantly different in the intercepts. There were more female than male specimens (1.3:1). Age determination was conducted using the otoliths. Marginal increment (MI) declined in summer and winter, which suggests that two rings are formed each year. Ages of sampled individuals ranged from 1 to 5 years. Length‐at‐age data were fitted using the von Bertalanffy growth model. The estimated growth functions were L_t = 19.93 [1 ? exp^{?0.21 (t + 0.811)}] total length and wet weight was females, and L_t = 16.47 [1 ? exp^{?0.32 (t + 0.499)}] for males.     

Synthesis and characterization of oligodeoxyribonucleotides containing terminal phosphates. NMR, UV spectroscopic and thermodynamic analysis of duplex formation of [d(pGGAATTCC)]2, [d(GGAATTCCp)]2 and [d(pGGAATTCCp)]2.

Derivatives of the oligomer [d(GGAATTCC)]2 with 5' (5'-P), 3' (3'-P) and both 5' and 3' (5',3'-P2) terminal phosphate groups have been synthesized and studied by temperature dependent UV and NMR spectroscopic methods. Thermodynamic studies of the helix to strand transition indicate that addition of 3' phosphate groups has very little effect on the delta G degree for helix formation at 37 degrees C while addition of 5' phosphate groups adds approximately -0.5 kcal/mole to the delta G degree for duplex formation. The helix stabilization by 5' phosphate groups occurs at salt concentrations of 0.1 M and above, and is primarily enthalpic in origin. Tm studies as a function of ionic strength also indicate that the oligomers fall into two groups with the parent and 3'-P derivatives being similar but less stable than the 5'-P and 5',3'-P2 derivatives. Imino proton and 31P NMR studies also divide the oligomers into these same two groups based on spectral comparisons and temperature induced chemical shift and linewidth changes. 31P NMR analysis suggests that addition of 5' phosphate groups results in a small change in phosphodiester torsional angles in the g,t to g,g direction, indicating improved base stacking at the 5' end of the modified oligomer. No such changes are seen at the 3' end of the oligomer on adding 3' phosphate groups.     

Synthesis, characterization, DNA-binding and photocleavage studies of [Ru(bpy)2(PPIP)]2+ and [Ru(phen)2(PPIP)]2+

A novel ligand 2-(4'-phenoxy-phenyl)imidazo[4,5-f][1,10]phenanthroline (PPIP) and its complexes [Ru(bpy)(2)(PPIP)](2+) (1) (bpy = 2,2'-bipyridine) and [Ru(phen)(2)(PPIP)](2+) (2) (phen = 1,10-phenanthroline) have been synthesized and characterized by mass spectroscopy, (1)H NMR and cyclic voltammetry. The interaction of two complexes with calf thymus DNA (CT-DNA) was investigated by spectroscopic and viscosity measurements. The results suggest that both complexes bind to DNA via an intercalative mode. Both complexes have also been found to promote the photocleavage of plasmid pBR 322 DNA under irradiated.     

Genetic diversity and population structure in the mtDNA control region of Liza haematocheilus (Temminck & Schlegel, 1845)

The redlip mullet (Liza haematocheilus) is a commercial marine species widespread in the Northwestern Pacific. The genetic diversity and population structure of the redlip mullet collected from 2007 to 2010 along Chinese and Japanese coastal regions, were investigated by mitochondrial DNA. A total of 82 L. haematocheilus individuals were collected from five locations and 41 haplotypes were obtained. A pattern of distribution of genetic variability with high level of haplotype diversity (0.9642 ± 0.0104) and moderate nucleotide diversity (0.0162 ± 0.0085) was detected. The minimum spanning tree constructed with 41 haplotypes showed three divergent clades, corresponding to those defined in the NJ tree. Analyses of molecular variance and the population statistic F_ST also revealed significant genetic structures among populations of L. haematocheilus. The demographic history of L. haematocheilus was examined using neutrality tests and mismatch distribution analysis, which indicated a Pleistocene epoch population expansion. Comparisons of the Hakodate and Qingdao populations in different years demonstrated that marginal but significant (P < 0.05) differences exist in the two Qingdao populations, but with no significant difference (P > 0.05) in the Hakodate populations. Knowledge of their genetic diversity and genetic structure is crucial to establishing appropriate fishery management for the species.     

Structural effects on electrochemical properties of the carboxamide complexes [Ni(Mebpb)] and [Ni(Mebqb)]

Two Ni(II) complexes of the dianionic ligands, Mebpb²⁻, [H₂Mebpb = N,N′-bis(pyridine-2-carboxamido)-4-methylbenzene] and Mebqb²⁻, [H₂Mebqb = N,N′-bis(quinoline-2-carboxamido)-4-methylbenzene] have been synthesized and characterized by elemental analyses, IR, and UV-Vis spectroscopy. The crystal and molecular structures of [Ni(Mebpb)], (1), and [Ni(Mebqb)], (2), were determined by X-ray crystallography. Both complexes exhibit distorted square-planar NiN₄ coordination figures with two short and two long Ni-N bonds (Ni-N ∼1.84 and ∼1.95 Å, respectively). The electrochemical behavior of these complexes with the goal of evaluating the structural effects on the redox properties has been studied.     

水稻二化螟［Chilo suppressalis（Walker）］发生期预测模型的探讨

本文利用福建省永安市１９７８－１９８８年诱虫灯下二化螟蛾发生期资料和气象资料,通过影响因子与预测对象的相关分析来选择初选因子．再应用逐步判别分析方法建立第一代二化螟蛾发生期的预测模型。经对历史资料的回报检验,该模型的判别率达９０．１－１００％;经１９８９和１９９０年实报,预报等级符合实际发生等级。     

Nitrogen mustard fixes the Z-conformation in poly[d(G-C)]poly[d(G-C)] and DNA]

The reactions of poly(dG-dC).poly(dG-dC) and (dG-dC)10 insert in the plasmid pGC20 with N-methyl-bis(2-chloroethyl)-amine (nitrogen mustard, HN-2) have been studied. It is shown that nitrogen mustard does not induce the B----Z transition in poly(dG-dC).poly(dG-dC), but produces fixation of the polynucleotide Z-conformation once this exists. In the case of pGC20 plasmid DNA, nitrogen mustard also fixes Z-form of the (dG-dC)-insert. The rate constant of the reaction of nitrogen mustard with guanine in the polynucleotide (k = 9,0.10(-3) min-1) is about one-third of that for the fixation of Z-form of the (dG-dC)-insert in the plasmid (k1 = 2,8.10(-2) min-1) which is attributed to a greater rate of formation of diguanyl derivative in the opposite DNA chains. It is suggested that nitrogen mustard is capable of fixing the Z-form DNA not only in vitro, but also in vivo.     

Analysis of [3',3'-d(2)]-nicotine and [3',3'-d(2)]-cotinine by capillary liquid chromatography-electrospray tandem mass spectrometry

A selective and sensitive LC/MS/MS assay was developed for the quantification of d(2)-nicotine and d(2)-cotinine in plasma of current and past smokers administered d(2)-nicotine. After solid phase extraction and liquid-liquid extraction, HPLC separation was achieved on a capillary hydrophilic interaction chromatography phase column. The analytes were monitored by tandem mass spectrometry with electrospray positive ionization. Linear calibration curves were generated for d(2)-nicotine (0.03-6.0 ng/ml plasma) and d(2)-cotinine (0.15-25 ng/ml plasma). The lower limits of quantitation were 0.15 ng/ml and 0.25 ng/ml for d(2)-nicotine and d(2)-cotinine, respectively. The coefficient of variation was 3.7% for d(2)-nicotine and 2.5% for d(2)-cotinine. The method was applied to two ongoing studies of d(2)-nicotine metabolism in prior and current smokers. Preliminary analysis of a subset of subjects from these studies detected a significantly lower rate of nicotine conversion to cotinine by past smokers compared to current smokers.     

Linear dichroism demonstrates that the bases in poly[d(AC)] · poly[d(GT)] and poly[d(AG)] · poly[d(CT)] are inclined from perpendicular to the helix axis

Flow linear dichroism is used to measure specific inclinations for each of the four bases in poly[d(AC)]·;poly[d(GT)] and poly[d(AG)]·poly[d(CT)] in both the B and A forms. For the B form in solution the bases are found to have a sizable inclination. Inclination is increased in the A form, as expected. In all cases the pyrimidines are more inclined than the purines. © 1993 John Wiley & Sons, Inc.     

CD Spectral Comparisons of the Acid-Induced Structures of Poly[d(A)]Poly[r(A)], Poly[d(C)], and Poly[r(C)]

Abstract

CD spectra were used to compare the acid-induced structural transitions of poly[d(A)] and poly[d(C)] with those of poly[r(A)] and poly[r(C)], respectively. The types of base pairing were probably the same in the acid self-complexes of both A-containing polymers and in the acid self-complexes of both C-containing polymers. Similar base pairings were indicated by similarities in the difference CD spectra showing the changes during the first major acid- induced transitions of the polymers. Information from the CD spectra and pK_a values of the transitions suggested that the transitions for the RNA polymers involved similar structural changes. The two DNA polymers were markedly different. Single-stranded poly [d(A)] was in the most stacked structure and had the lowest pK^a for forming an acid self-complex. Single-stranded poly[d(C)] was in the least stacked structure and had the highest pK_a for forming a protonated duplex.     

Psi compaction of poly[d(AT)].poly[d(AT)]

The compaction of poly[d(A–T)] · poly[d(A–T)] by Co(III) is accompanied by the formation of ψ(+)- and ψ(-)-structures. The chirality of the ψ-structure depends on the Co(III) concentration, ionic strength, temperature, pH, and the chain length of the polymer. The two forms can be readily interconverted by manipulating these factors. Phase diagrams have been constructed that demonstrate the regions of stability of the enantiomers as a function of two variables, while other factors are held constant. At critical points in the phase diagram the two forms are in such unstable equilibrium that mechanical motion will cause ψ(+) ? ψ(-) interconversion. The formation of both ψ(+)- and ψ(-)-structures by the action of Co(III) on poly[d(A–T)] · poly[d(A–T)] contrasts markedly with the behavior of poly[d(G–C)] · poly[d(G–C)] in similar circumstances by forming only the ψ(+)-structure and that of native DNA to produce no ψ at all. Thus the base sequence is important in determining the structure of chirally associated DNA molecules.     

Amino acid-specific ADP-ribosylation. Sensitivity to hydroxylamine of [cysteine(ADP-ribose)]protein and [arginine(ADP-ribose)]protein linkages

Hydroxylamine stability has been used to classify (ADP-ribose)protein bonds into sensitive and resistant linkages, with the former representing (ADP-ribose)glutamate, and the latter, (ADP-ribose)arginine. Recently, it was shown that cysteine also serves as an ADP-ribose acceptor. The hydroxylamine stability of [cysteine([32P]ADP-ribose)]protein and [arginine([32P] ADP-ribose)]protein bonds was compared. In transducin, pertussis toxin catalyzes the ADP-ribosylation of a cysteine residue, whereas choleragen (cholera toxin) modifies an arginine moiety. The (ADP-ribose)cysteine bond formed by pertussis toxin was more stable to hydroxylamine than was the (ADP-ribose)arginine bond formed by choleragen. The (ADP-ribose)cysteine bond apparently represents a third class of ADP-ribose bonds. Pertussis toxin ADP-ribosylates the inhibitory guanyl nucleotide-binding regulatory protein (Gi) of adenylate cyclase, whereas choleragen modifies the stimulatory guanyl nucleotide-binding regulatory protein (Gs). These (ADP-ribose)protein linkages are identical in stability to those formed in transducin by the two toxins, consistent with the probability that cysteine and arginine are modified in Gi and Gs, respectively. Bonds exhibiting differences in hydroxylamine-stability were found in membranes from various non-intoxicated mammalian cells following incubation with [32P]NAD, which may reflect the presence of endogenous NAD:protein-ADP-ribosyl-transferases.     

Respiratory responses and tolerance to hypoxia in two marine teleosts,Epinephelus akaara (Temminck & Schlegel) and Mylio macrocephalus (Basilewsky)

The respiratory responses and tolerance of hypoxia were studied in two marine teleosts, the red grouper (Epinephelus akaara, a sluggish species) and the black sea bream (Mylio macrocephalus, an active species). Neither species showed abnormal behaviour or mortality when exposed to 2 mg O₂ l^–1 for 7 h. The black sea bream was, however, comparatively more tolerant when exposed to 1 mg O₂ l^–1, but tolerance of both species became similar under extremely hypoxic conditions (i.e. 0.5 mg O₂ l^–1). In contrast to most other teleosts, both species showed a reduction in opercular beating rate during hypoxia, and oxygen conformity was found in the range of 0.5 to 7.0 mg O₂l ^–1. O₂ dissociation curves were constructed, and the P₅₀ value of the black sea breams (27 ± 5.6 mm Hg) was found to be much lower than that of the red groupers (50 ± 2.5 mm Hg). For both species, the general levels of venous PO₂ showed a direct relationship to ambient PO₂, and were markedly reduced after 1 h exposure to various levels of hypoxia. Compared with the red groupers, the black sea breams appeared to be more able to maintain its venous PO₂ levels during prolonged hypoxic exposure.     

The [Re(N)(PN)] building-block

The formation of the uncommon molecular ion fragment [Re(N)(P^∩N)] is ESI-MS conditions is confirmed by the synthesis and characterization of the representative [Re(N)Cl₂(P^∩NMe₂)PPh₃] complex. This species contains the unprecedented [Re(N)(P^∩NMe₂)] moiety which constitutes an additional example of metal-based building-block potentially useful in the design of rhenium radiopharmaceuticals.